2393-6304 2393-6304 S2393-63042016000200056 10.22235/ao.v13i2.1308 Ecuador Ecuador Ecuador Ecuador 00 00 2016 00 00 2016 13 2 56 62

1994 64 1 1 31-42 2008 45 2 2 2010 Junio 21-25 La Habana 2006 p. 1-9 1988 1991 99 5 5 387-401 1994 2a ed.